In Ubuntu Studio 22.10 and 22.04.1 LTS Every time I run apt, especially apt update I find it has looked for a source that does not exist anywhere in /etc/apt/ directories or files therein.
At first this was just a puzzling irritant but now Ubuntu Studio Discovery is delayed as much as 3 minutes opening apparently looking for the same source.
$ sudo apt update
Hit:1 http://us.archive.ubuntu.com/ubuntu kinetic InRelease
Hit:2 http://us.archive.ubuntu.com/ubuntu kinetic-updates InRelease
Get:3 http://us.archive.ubuntu.com/ubuntu kinetic-backports InRelease [99.9 kB]
Hit:4 http://security.ubuntu.com/ubuntu kinetic-security InRelease
Ign:5 http://archive.canonical.com/ubuntu kinetic InRelease
Err:6 http://archive.canonical.com/ubuntu kinetic Release <<---!!
404 Not Found [IP: 2620:2d:4000:1003::111 80]
Hit:7 https://ppa.launchpadcontent.net/tatokis/alarm-clock-applet/ubuntu kinetic InRelease
Reading package lists... Done
E: The repository 'http://archive.canonical.com/ubuntu kinetic Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
I tried the various recommendations for sudo ppa-purge and sudo apt-get install ppa-purge and received results indicating they failed because they could not find the package to purge.
Checking "Software Sources" I found this source was not listed under any of the tabs.
I then looked in each directory and file in /etc/apt/ and again found no sign of this
"http://archive.canonical.com/ubuntu kinetic Release"
So the questions are
"Where is apt finding the directive to look for this?"
and
"How do I remove it, so apt does not continue looking for it?"
Below is a log of the directories and files I searched to confirm that "http://archive.canonical.com/ubuntu kinetic Release" is not listed in the Ubuntu Sources or in /etc/apt/.
Contents of apt sources.list
$ inxi -r
Repos:
Active apt repos in: /etc/apt/sources.list
1: deb http://us.archive.ubuntu.com/ubuntu/ kinetic main restricted
2: deb http://us.archive.ubuntu.com/ubuntu/ kinetic-updates main restricted
3: deb http://us.archive.ubuntu.com/ubuntu/ kinetic universe
4: deb http://us.archive.ubuntu.com/ubuntu/ kinetic-updates universe
5: deb http://us.archive.ubuntu.com/ubuntu/ kinetic multiverse
6: deb http://us.archive.ubuntu.com/ubuntu/ kinetic-updates multiverse
7: deb http://security.ubuntu.com/ubuntu/ kinetic-security main restricted
8: deb http://security.ubuntu.com/ubuntu/ kinetic-security universe
9: deb http://security.ubuntu.com/ubuntu/ kinetic-security multiverse
10: deb http://us.archive.ubuntu.com/ubuntu/ kinetic-backports main restricted universe multiverse
11: deb http://archive.canonical.com/ubuntu/ kinetic partner
Active apt repos in: /etc/apt/sources.list.d/tatokis-ubuntu-alarm-clock-applet-kinetic.list
1: deb https://ppa.launchpadcontent.net/tatokis/alarm-clock-applet/ubuntu/ kinetic main
I searched in /etc/apt/and sub directories
for http://archive.canonical.com/ubuntu kinetic Release
g905:/etc/apt$ ls
apt.conf.d keyrings sources.list sources.list.d trusted.gpg.d
auth.conf.d preferences.d sources.list~ trusted.gpg
g905:/etc/apt$ cd trusted.gpg.d
g905:/etc/apt/trusted.gpg.d$ ls
tatokis-ubuntu-alarm-clock-applet.gpg ubuntu-keyring-2012-cdimage.gpg
tatokis-ubuntu-alarm-clock-applet.gpg~ ubuntu-keyring-2018-archive.gpg
g905:/etc/apt/trusted.gpg.d$ cd ..
g905:/etc/apt$ ls
apt.conf.d keyrings sources.list sources.list.d trusted.gpg.d
auth.conf.d preferences.d sources.list~ trusted.gpg
g905:/etc/apt$ cd sources.list.d
g905:/etc/apt/sources.list.d$ ls
tatokis-ubuntu-alarm-clock-applet-kinetic.list
g905:/etc/apt/sources.list.d$ cd ..
g905:/etc/apt$ cd apt.conf.d
g905:/etc/apt/apt.conf.d$ ls
01autoremove 20archive 50appstream 60icons-large 99update-notifier
01-vendor-ubuntu 20auto-upgrades 50command-not-found 60icons-large-hidpi
10periodic 20dbus 50unattended-upgrades 70debconf
15update-stamp 20packagekit 60icons 88libdvdcss-pkg
20apt-esm-hook.conf 20snapd.conf 60icons-hidpi 99synaptic
g905:/etc/apt/apt.conf.d$ cd ..
g905:/etc/apt$ cd auth.conf.d
g905:/etc/apt/auth.conf.d$ ls [Empty]
g905:/etc/apt/auth.conf.d$ cd ..
g905:/etc/apt$ cd preferences.d
g905:/etc/apt/preferences.d$ ls [Empty]
g905:/etc/apt/preferences.d$ cd ..
Again to be clear; Where else can it be? and If more than just deleting the folder or file, How can I delete it.
Platform details
Operating System: Ubuntu Studio 22.10
KDE Plasma Version: 5.25.5
KDE Frameworks Version: 5.98.0 Qt Version: 5.15.6
Kernel Version: 5.19.0-1018-lowlatency (64-bit)
Graphics Platform: X11
Processors: 24 × AMD Ryzen 9 7900X 12-Core Processor
Memory: 31.1 GiB of RAM
Graphics Processor: llvmpipe
Manufacturer: MicroElectronics Product Name: G905 System Version: 1.0